In Veronica Roth’s best-selling "Divergent" series, teenagers in dystopian Chicago must choose which faction best represents them based on one of five personality traits.

In J.K. Rowling's universe, students at Hogwarts School of Witchcraft and Wizardry are sorted into one of four houses by a magical hat that sees inside their heads.

Again and again in young adult books, people are separated, classified and labeled — from the 12 districts of Panem in "Hunger Games" to the "Uglies," "Pretties" and "Specials" in Scott Westerfield's best-selling series.

What makes these stories resonate with modern-day teens and adults? They speak to shared experiences and our attempts to simplify the world around us.

Labels like "jocks," "preps" and "slackers" might seem to be the stuff of a high-school cafeteria, but although the terms may have changed, labels persist later in life.

Robert Faris, a sociologist at the University of California, says such labeling behavior isn't exclusive to adolescence.

"If you put adults in a similar situation, you'd find similar [labeling] behaviors," he said in New York Magazine. "It's not adolescence that’s the problem. It’s the giant box of strangers."

Princesses, brains and criminals

According to psychologists, we assign labels to social groups during adolescence because our teenage years are when we begin to construct our identities.

We need a way to navigate our lives — and the cafeteria — so we assign people labels, and those labels come with certain expectations.

During high school, our prefrontal cortex, the area of the brain that regulates impulse control and self-reflection, undergoes a lot of changes. On top of that, our brains are buzzing with dopamine.

These dopamine-addled brains make experiences more intense and the stakes of self-identification even higher. Just like in "Divergent" and other young adult books, decisions about who we are seem like they could seal our fates.

And there may be some truth to that.

A 2000 University of Arizona study found that stereotypes might have a predictive quality. Researchers asked a group of high school sophomores to select the "Breakfast Club" character they most identified with, using labels like "princesses," "brains" and "criminals."

Eight years later, they asked the participants the same question and found that, for the most part, identities had solidified.

"The predictive power of our construct suggests we have tapped something important — perhaps a perceptual construct through which adolescents encode, by way of social construct, pervasive matters of personal choice and agency," the authors wrote.

What taking that Buzzfeed quiz says about you

Stories with strong identity themes like "Divergent" are understandably appealing to teens undergoing journeys of self-discovery, but the wide appeal of such stories speaks to how universal these adolescent experiences are.

Young adult books are experiencing a period of unparalleled popularity, and more than half the buyers of YA books (55 percent) are over the age of 18, according to a 2012 study (30- to 44-year-olds account for 28 percent of sales).

And they're not just purchasing books for teens — when asked the intended recipient of the books, 78 percent identified themselves.

This collective quest to discover and reconfirm our identities throughout life can be seen in the resurgence of quizzes on sites like Buzzfeed that classify us by everything from what kind of cookie we are to what color our aura is.

And it's not just Millennials who want to know if they're a chocolate chip cookie or a coconut macaroon.

People of all ages are taking quizzes, and even publications like the New York Times have benefited from giving people an opportunity to classify themselves. In fact, the most popular item the Times published in 2013 was a quiz.

These quizzes — merely novelty versions of psychological personality tests — are the easily accessible Sorting Hats and Choosing Ceremonies of the real world. But why do we spend our time answering questions that are in no way accurate predictors of our personalities?

Because we want to know who we are and be able to identify those like us. We want to declare, "I am a Gryffindor therefore I am brave" or "I, too, am a snickerdoodle because I enjoy both parties and Netflix marathons."

This quest to categorize ourselves stems from a desire for community that can be especially fervent during adolescent years.

As family dynamics change and high school relationships are established and broken, there's a strong urge to find the people you belong with. Studies show the group you identity with as a teenager can have significant implications for you both academically and behaviorally.

Just as joining the marching band or sitting with the jocks makes a statement about who you are in high school, so can taking and sharing quizzes on social media allow us to instantly affirm that we identify with a certain Divergent faction, Hogwarts house or dessert.

But what if, as a fan of the Harry Potter series for example, you already know that you are a bookish and intelligent and are no doubt a Ravenclaw. Why then take a sorting quiz?

Psychologists say it's because we're constantly seeking feedback that confirms our views of ourselves. By thoughtfully selecting our quiz answers, we can likely generate the result we want, and our brains take pleasure in knowing that we know ourselves.

Determining personality

While a Buzzfeed quiz can't offer insight into your true character, is there any personality test that can?

Perhaps the most well-known personality test is the Myers-Briggs Type Indicator, which was developed in the 1920s and has been continually updated since then.

The Myers-Briggs classifies people as one of 16 personality types based on four scales: extraversion vs. introversion, sensing vs. intuition, thinking vs. feeling and judging vs. perceiving.

More than 2.5 million people take the test each year, but is it a true indicator of personality? It depends on whom you ask.

Some psychologists argue that if a person answers honestly, the test can provide useful information.

However, the test has faced criticism because people can take the tests at different times and get different outcomes.

I've taken the Myers-Briggs twice and received varying results. In 2001, I was classified as an ENFP. In 2013, I was labeled an INFJ. Has my personality changed, was I simply more honest in my responses, or is there a flaw in the test? This is what researchers in the field of personality psychology are trying to determine.

Interestingly, our drive to categorize ourselves and find our place in the world is at odds with our desire to be unique, especially in American culture where individualism is highly regarded.

We seek connectedness and harmony with others — what psychologists call belongingness — but we also want to be one of a kind, and we often value those who march to the beat of a different drummer.

You see this dichotomy in young adult literature as well. Divergent's protagonist, Tris, struggles to identify which faction is her best fit because she is "divergent," meaning her test results couldn't classify her.

When the Sorting Hat is placed upon Harry Potter's head, the magical object states that he could be either a Gryffindor or a Slytherin.

In the end, it is the choices Tris and Harry make that reveal their true selves, and in doing so, the characters teach us a valuable lesson: While finding our place in the world is important, placing too much emphasis on those labels can be dangerous.

Michael Ashton, a psychologist at Brock University, says that personality researchers have found that despite our desire to classify ourselves, people don't fit into boxes.

"Each person can be measured on about six basic personality traits, each of which is a continuum. In combination with each other, these half-dozen trait dimensions produce a huge variety of personalities," he said.

In short, no matter which faction or house we identify with — or what baked treat we eat for dessert — it boils down to is this: We are all "Divergent."